style.css

*{
    margin: 0;
    padding: 0;
    font-family: poppins;
    box-sizing: border-box;
    font-weight: 500;
    /* color: white; */
}

.container{
    width: 100%;
    min-height: 100vh;
    background: hsla(355, 74%, 62%, 1);

    background: linear-gradient(0deg, hsla(355, 74%, 62%, 1) 0%, hsla(0, 0%, 3%, 1) 100%);
    padding: 20px;  
    display: flex;
    align-items: center;
    justify-content: center;
    /* position: fixed; */
}
.todo{
    width: 100%;
    min-height: 40rem;
    background-color: white;
    margin: 10rem;
    border-radius: 0.8rem;
    /* display: flex; */
    /* justify-content: center; */
    /* align-items: center; */
    color: rgb(239, 105, 116);
    position: relative;
    padding: 20px;
}

.todo h2{
    font-size: 1.5rem;
    margin-top: 0.5rem;
    margin-left: 1rem;
    user-select: none;
}
.todo h2 i{
    padding-left: 1rem;
    color: brown
}
.task{
    display: flex;
    align-items: center;
    justify-content: space-between;
    background-color: rgb(230, 227, 227);
    border-radius: 1.5rem;
    padding: 1rem;
    margin: 1rem 0;
}
input{
    border: none;
    flex: 1;
    outline: none;
    background-color: transparent;
    padding: 0.5rem;
}
button{
    border: none;
    outline: none;
    padding: 1rem 2rem;
    border-radius: 2rem;
    background-color: tomato;
    color: white;
    font-size: 1rem;
    cursor: pointer;
}
button:hover{
    background-color: orangered;
}
ul{
    padding: 0;
}
ul li{
    list-style: none;
    font-size: 1.1rem;
    padding: 0.8rem 0.5rem 0.5rem 2.5rem;
    cursor: pointer;
    user-select: none;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-right: 1rem;
    
}
ul li::before{
    content: '';
    position: absolute;
    height: 0.9rem;
    width: 0.9rem;
    border:1px solid black;
    border-radius: 50%;
    left: 0.5rem; /* Adjust left position */
    top: 50%; /* Center vertically */
    transform: translateY(-50%);
}
ul li.check{
    color: #555;
    text-decoration: line-through;
}
ul li.check::before{
    background-color: black;
}
ul li span{
    font-size: 2rem;
    border-radius: 30%;
}
ul li span:hover{
    background-color:#edeef0;
}
@media(max-width:800px){
   .container{
    padding: 10px;
   }
   .todo{
    width: 100%;
    max-width: 25rem;
    min-height: 20rem;
   }
   button{
       padding-right:2rem;
   }
}